Fig. 2

a Biogeographic regions used in the RASP analysis: A = western North America, B = eastern North America, C = southeastern Mexico and Central America, D = West Indies, and E = South America. b Chronogram of the Mellisugini lineages based on the third calibration method (secondary calibration + substitution rates) with a Yule speciation model for the combined ND2 and ND4 mitochondrial genes and FBG I7, AK1 I5, ODC1, and MUSK I3 nuclear loci data set. Purple bars indicate 95% Highest Posterior Density (HPD) intervals for selected nodes. The pink dotted vertical lines denote the time span of the Pliocene. Results using Bayesian methods with BBM (Bayesian Binary MCMC) analyses implemented in RASP [55] are drawn on this topology. The ancestral origin for each taxon, as delimited in (a), is shown on the terminal lineages. Pie charts at nodes represent the probabilities of the ancestral distributions. These probabilities account for the phylogenetic uncertainty in the rest of the tree and the biogeographic uncertainty at each node. Asterisks next to main nodes refer to posterior probability support for each node (* > 0.8 posterior probability). Painting by Marco Pineda (courtesy of Juan Francisco Ornelas) showing Calothorax pulcher (male)